It is known that lasers can be used to produce glass pH electrodes by melting a glass membrane in close contact with a glass casing, a line seal being effected. See Sangermano et al., U.S. Pat. No. 3,876,409, assigned to the assignee of the present application, and incorporated herein by reference.
One of the major limitations on the use of inorganic bonded silica materials, e.g., reconstituted mica paper for commutator segment plate or side mica is the excessive wear on undercutting tools, such as saws and the like. It would be of significant advantage to be able to undercut such materials without the need to expend such tools and such an advantage is an object of the present invention.